A young man, longing for adventure rather than immediately take over his millionaire uncle's business in San Francisco, chooses to explore a tropical island his uncle purchased. As soon as they get to the shore of the island the ship is attacked by really fake looking gillmen--and the man and his schoolteacher jump overboard. On the island they discover giant fake looking monsters that look like those plastic blow up Godzillas, giant caterpillars and cannibalistic natives. They befriend one of the natives after rescuing him from an enemy tribe and then discover a young woman who has been stranded on the island for the past year. Whew. It turns out that the mystery is that everything was a set up by the man's uncle--all the monsters were giant robotic toys and the cannibals were really actors, a facade just so he could learn to be independent. Agggghhh.